<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script>
        // 数字类型
        console.log(Number.MAX_VALUE);
        console.log(Number.MIN_VALUE);
        var num = 18;
        // 布尔型
        alert(isNaN(num));
        // string
        var str = '我是 高\n富\\帅';
        alert(str);
        var str1 = 'my name is dimingda';
        // 查看字符串长度
        alert(str1.length);
        // 字符串拼接
        var firstName = 'di';
            lastName = 'mingda';
        alert(firstName + lastName);
        alert(typeof(firstName));
    </script>
</head>
<body>
    
</body>
</html>